Integral vacuum pump and air compressor



March 28, i967 R, A. MOFFATT 3,31L293 INTEGRAL VACUUM PUMP AND AIRCOMPRESSOR -qif 5 CU r3 4a 44 40 [Il C] ATTORNEYS March 28, 1957 R, A,MOFFATT 3,311,293

INTEGRAL VACUUM PUMP AND AIR COMPRESSOR Filed Aug. e, 1965 2Sheets-Sheet 2 ATTORNEYS United States Patent O 3,311,293 INTEGRALVACUUM PUMP AND AER CMPRESSR Robert Alexander Moffatt, St. Joseph,Mich., assignor to Gast Manufacturing Corporation, Benton Harbor, Mich.,a corporation of Michigan Filed Aug. 6, 1965, Ser. No. 477,737 24Claims. (Cl. 23u- 209) This invention relates to rotary pumping devicessuch as may be used to produce either vacuum or pressure, of theintegral type in which the pumping apparatus and its driving motor aremade in a single integral unit having a single drive shaft, and moreparticularly to a new and unique type of integral pump which providesheavy-duty operation and incorporates new concepts in bearing retentionand cooling, to provide for extremely long life under hard usage.

In the past, integral rotary pumping means have been devised forapplication in instances where limited capacities are sufficient. Suchintegral apparatus has decided advantages in being more compact andeflicient than the conventional separate motor and pump which arecoupled together for cooperative operation. However, the integral typeof pump has serious problems and wellknown limitations when utilized inheavy-duty applications where rigorous use and high capacities arerequired,

These limitations include the following conflicting requirements.Heavy-duty applications result in the production of considerable heat atthe pump rotor. Typically, the rotor is mounted closely adjacent themotor part of the integral apparatus with a support bearingtherebetween, and the heat from the rotor usually is conducted directlyto this bearing. Little or no actual heat relief or isolation isprovided, and consequently under the increased heat from higher loads,the bearings very soon fail.

This problem is aggravated and compounded by the fact that in integralpumping apparatus the most preferred configuration is to use acantilevered or overhanging type of drive shaft, in which the shaft isunsupported at the end extremity of the pump portion. This has thedesirable feature of eliminating the customary bearing in the end capfor the pump. Thus, in servicing the rotor, as for example to replaceworn-out vanes and the like, all that is required is merely to loosenand remove the end cap, there being no bearing to create replacement oralignment problems during the service operation. While the cantileveredtype of construction has heretofore been feasible in light-dutyapparatus, under the more severe conditions of heavy-duty operation theloading effects placed upon the rotor soon causes misalignment of thedrive shaft, with attendant cocking of the rotor. Together with theincreased heat to which the main internal bearing (between the motor andthe pump portions) is subjected, the early malfunction and failure ofsuch pumps becomes understandable and predictable.

Accordingly, it is a major object of the present invention to provide anintegral motor and pump apparatus for extended heavy-duty appiication,having new design features which obviate the necessity of any bearing inthe end-cap assembly to provide a cantilevered or overhung drive shaftarrangement.

Another important object of the present invention is to provide aheavy-duty integral motor and pump apparatus of the foregoing type, inwhich is incorporated a new and unusual manner of cooling the bearingsupporting the drive shaft between the motor and pumping portion.

Still another object of the present invention is to ice provide anintegral pump apparatus of the foregoing type in which the said bearingis mounted, supported, and retained in a manner tending to isolate itfrom the heat of the rotor assembly.

A further important object of the present invention is to provide anintegral motor and pump apparatus of the foregoing type having a new andunusual drive shaft seal conguration for such usage, and includingunique structure for isolating the said bearing from the drive shaftseal, in order to prevent lubricant and contaminants from the pumpingportion of the apparatus from coming into Contact with and fouling thebearing.

Still another important lobject of the present invention is to provide aunique new support structure for use in integral motor and pumpingapparatus, by which the bearing for supporting the drive shaft isretained in a desired aligned position within a hub structure. The novelsupport structure provides heat-radiating means for conducting the heataway from the bearing, while simultaneously providing passageways bywhich cooling air may be brought into proximity with the bearing andwith the heat-radiating structure, to greatly facilitate the cooling ofthe bearing.

A further important object of this invention is to provide an integralmotor and pumping unit having the foregoing attributes and furtherincluding a fan means which is mounted internally within the unit so asnot to interfere with its serviceability, and which draws cooling airthrough the pumping portion and over the supporting structure. Theintegral unit further includes an internal baie means positioned atleast partly in the ow of cooling air, which serves to deect and directthe cooling air over the bearing and its supporting structure in adesired manner.

The foregoing major objects of the invention, together with the manyadvantages inherent therein, as well as numerous other objects and otherdesirable attributes thereof, will become increasingly clear followingconsideration of the ensuing specification and its appended claims,particularly when taken in conjunction with the illustrative drawingssetting forth a preferred embodiment of the invention.

In the drawings:

FIG. l is a side elevation of a first form of integral motor and pumpingapparatus, portions thereof being broken away and shown in section toillustrate various details;

FIG. 2 is an enlarged, fragmentary side elevation of a second type ofintegral motor and pumping apparatus, showing further details of theinvention;

FIG. 3 is a front elevation of the novel bearing spacing and supportstructure of the invention, as seen from the right relative to FIG. l;

FIG. 4 is a side elevation of the structure of FIG. 3, taken through thesection IV-IV thereof;

FIG. 5 is a rear elevation of the structure of FIG. 3, as seen from theopposite side thereof; and

FIG. 6 is an enlarged sectional view showing a portion of the structureof FIG. l in more detail.

Briey stated, the present invention provides an integral vacuum pump/air compressor apparatus, of the type characterized by a single driveshaft having a motor means connected thereto for driving both the shaftand pumping apparatus connected to be driven by the same shaft. Theapparatus includes a fan structure mounted on the drive shaft near themotor means and between it and the pumping components, and a bearingsupport and spacing structure which is secured relative to the motormeans and which has portions extending toward and generally surroundingthe drive shaft to form a hub structure thereabout. A main supportbearing is retained in position by the aforementioned hub structure, andthis bearing serves to support the drive shaft in a desired alignment.Means defining a pump cylinder about the drive shaft is secured relativeto the said bearing support structure, and a rotor structure is mountedupon the shaft for movement therewith within the said cylinder. Asuitable end cap structure is provided, and this is positioned adjacentthe cylinder-defining means and secured relative thereto, forprotectively enclosing thev end of the apparatus. Thus, the drive shaftextends substantially through the rotor structure and the cylindercavity, but is unsupported at this end of the apparatus. Instead, theaforementioned main support bearing provides all of the required supportfor the cantilevered or overhung drive shaft. Moreover, the said bearingsupport and retaining structure retains the main support bearing with adefinite and fixed spacing between it and the rotor structure, so thatthe bearing is effectively isolated from the relatively high heatproduced at the rot-or.

Further, when pumping components of the lubricated type are used in thepresent integral apparatus, the bearing-support structure provides forthe mounting and retention of a seal for preventing lubricants andcontaminants from the rotor assembly from entering and fouling the mainsupport bearing, and also for preventing air from entering or leavingthe pumping chamber, to thereby raise the pumping efficiency. Thesupport structure spaces the bearing from this seal, so as toeffectively isolate these two members. The novel support structureadditionally defines passages through which the cooling air drawn by theinternal fan means may ow to cool the hub and the bearing therein, andthe portions of the support structure extending toward the drive shaftserve to define cooling fins, by which the heat from the bearing may beabsorbed into the hub and from there into the fins, to be radiated intothe cooling air passing thereover.

The novel support structure further defines passageways communicatingwith the said passages which serve to allow the cooling air to come intocontact with and circulate about a portion of the main support bearingin the area where it is spaced from the rotor assembly and from thelubrication seal, for maximum bearing cooling. This structure providesan integral pump/compressor apparatus which will withstand heavy-dutyloading for very extended periods and has a particularly long servicelife due to the maximum cooling effect upon the main support bearing.The integral apparatus is also extremely easy to service, since the endcap structure contains no bearings or other parts liable to causealignment diiculties when reassembled, and when the cap is removed itimmediately exposes the interior of the rotor assembly for fast and easyrepair or maintenance thereof.

Referring now in more detail to the drawings, a complete integral vacuumpump/ air compressor apparatus 10 is illustrated in FIG. l. As will beseen, the integral apparatus 10 is of the lubricated type andincorporates the unique sealing means of the invention. The integralapparatus 10 has an electric motor portion 12 shown at the right in FIG.1, which includes a stand or frame structure 14 for mounting the entireapparatus.

It will be observed that a single drive shaft 16 extends through themotor portion 12 `and also projects outwardly therefrom. Immediatelyadjacent the motor portion, a fan apparatus 18 is mounted upon the driveshaft for movement thereby, as for example by being splined thereto. Theparticular structure of the internal fan 18 may be varied according tochoice, and its operation will appear more fully hereinafter. The novelsupport structure 20 is positioned about the drive shaft 16 immediatelyadjacent the fan means 18, and although the support structure is shownin more detail subsequently, it will be here observed that it hasportions extending inwardly toward the drive shaft to define a hub 22encircling the shaft. The main support bearing 24 is mounted within dhub 22, which retains it in the position shown in this figure.

As has been stated, the integral apparatus 10 of FIG. l is of the typehaving lubricated pumping components. Hence, a seal is required toprevent the entry of lubricant or air into the pump cavity, and. also toprevent contaminants from the rotor section from entering and foulingthe main bearing 24. A unique seal means 26 for achieving these purposesis illustrated generally in FIG. l and in detail in FIG. 6. As will benoted, this is preferably a double or dual construction, having a pairof symmetrical, opposing, angularly-disposed sealing portions 2S and 30,which are separated by a grease-filled cavity 32. The two sealingportions 23 and 30 contact and ride upon the drive shaft 16 to preventthe passage therealong of lubricant, aira and contaminants, and they arearranged in the angular relation shown so that one of them will bechiefly effective when the integral apparatus 10 is being used as avacuum pump, Whereas the other sealing portion will be principallyeffective when the apparatus is used as an air compressor.

It will be observed that the seal means 26 is positioned by and retainedwithin a second hub portion 34 defined by the support structure 20, andthat a definite xed isolating space 36 is maintained between the mainbearing 24 and the seal means 26. Thus, not only is the bearing isolatedfrom the seal with regard to lubricants and contaminants, but it is alsoisolated therefrom with regard to heat. v

Immediately adjacent the support structure 20 is positioned a statormeans 33 which denes a generally cylindrical cavity 40 therewithin,through which the drive shaft 16 passes. Within the cavity 4t) andaffixed to the drive shaft 16 for movement thereby, is a rotor structure42, of a known type. The rotor has a number of vanes 44 which are biasedoutwardly therefrom under the centrifugal force resulting from therotary movement of the rotor, and the vanes remain in contact with thesurface of the cylinder cavity as the rotor is driven in a rotary mannerby the drive shaft. As will be readily understood, this produces thedesired pumping or compressing operation.

It will be observed that the leftward lateral surface of the supportstructure 20 (as seen in FIG. 1) actually operates to close the cylindercavity 40 on its side adjacent thereto, and the end cap structure 46closes the cavity 40 on its other lateral side. As will be familiar tothose skilled in the art, the end cap structure 46 has appropriate inletand outlet ports formed therethrough, one of which is designated 48 inthe figure. The end cap structure also has suitable venting ports formedtherethrough (not specifically shown), through which outside air may bedrawn `by the action of the fan means 18 within the integral unit 1G. Inaddition to the detailed operation to be noted subsequently, such airpasses over the outside of the stator means 38, which preferably has aseries of radial cooling fins formed thereupon. Thus, the air initiallyserves to cool the stator means and, at least in part, the rotorstructure 42 operating therewithin.

As FIG. l further illustrates, the end cap structure 46 is secured inplace upon the integral apparatus 10 solely by a series of through-boltssuch as 52, whose heads `bear against appropriate seats 54 formed in theend surface of the cap, and which extend through passages formed in thestator 38 to thread into corresponding tapped holes 56 formed in thesupport structure 20 (note FIG. 5). The stator 3S is separately securedto the support structure 20 in a similar manner, by means of othertapped holes 58 formed in the latter (FIG. 5). Thus, the end capstructure may readily be removed `from the integral apparatus 10 byremoval of the tie bolts 52 to expose the stator and rotor, which remainintact. If it is desired to then remove the stator, this is quickly andeasily accomplished in a similar manner.

The fragmentary view of FIG. 2 illustrates the interior components of anintegral pump/compressor apparatus 111), which is of the non-lubricatedor oil-less type. Such `an apparatus is for the most part directlyanalogous to the integral apparatus 16 of FIG. 1, save for portions tobe noted presently. Thus, a drive shaft 16 extends from a motor portion(not shown), and a fan means 18 is mounted thereupon. A bearing supportstructure 12) much like the structure 2G of FIG. l is positionedadjacent the fan means 18, and this structure defines a central hubportion 122 'which positions and retains a main support bearing 24identical to that shown in FIG. l.

In the case of the non-lubricated type of apparatus, the threat of thelubrication creeping along the drive shaft `backward into the mainsupport lbearing is no longer present, and consequently no sealing meansas such is required between the bearing and the rotor (which isindicated at 142). Non-lubricated pumps generally utilize carbon orother similar vanes which are said to be self-lubricating, in that theygradually wear away during use and do not require auxiliary lubricantsbetween them and the interior of the cylinder cavity. Since particles ofthe material from which the vanes are made are likely to be foundthroughout the cavity, it is desirable to provide a barrier between therotor and the internal bearings, such as the main bearing 24. For thispurpose, a washer-like barrier plate 125 is provided, which encirclesthe drive shaft and is preferably press'itted into place thereupon, soas to lie within the space 136 between the bearing and the rotor.

It is to be noted that space between the barrier plate 125 and thebearing 24 is insured `by the abutment of the barrier against a shoulderportion 127 formed on the drive shaft 16. From this, it will be quiteapparent that the integral `apparatus 110 of FIG. 2 is essentially thesame as apparatus 19 of FIG. l, and except for the matter of the sealingmeans 26 in the latter, provides most of the important overall benefitswhich the apparatus l@ provides. These include the isolation of the mainsupport bearing from the rotor heat, the internal fan means which drawscooling air past the stator means and into proximity with the supportstructure hub and main support bearing, and the cantilevered or overhungdrive shaft arrangement which dispenses with the requirement of asupport bearing outboard from the rotor and stator assembly to provideunusually easy and foolproof serviceability features.

The novel bearing support and retention structure 2@ of the presentinvention is shown in considerable detail in FIGS. 3, 4, and 5, to whichreference is now made. The support structure 2i) is basically a somewhatfiat, circular structure having an outer rim portion 6i) extendingaround its periphery, which is positioned adjacent the fan means 18 (seeFIG. l). A series of generally hat fins 62 extends from the outer rim6i? toward the center of the support structure, and at their inward endsthese fins merge to define the hub 22 for the main support bearing 24,and also the hub 34 which may be used in connection with the sealingmeans 26.

By examining FIGS. 4 and 5, it will be noted that the arrangement of thefin structures 62 is such that open passages 64 are provided betweeneach two adjacent fins. Moreover, in FIG. 4 it will be seen that thespacing 36 maintained between the main support bearing 24 and thesealing means hub 34 in effect provides a passageway which actuallycommunicates with the underside of the bearing 24. The passages 64 andpassageways 36 are also in communication with each other, andconsequently the current of cooling air produced by the fan means 18 isfree to pass through the passages 64, over the fins 62, and into thepassageways 36.

The cooling eiect upon the bearing 24 produced in this manner is thusclear-ly a very considerable one. In the first place, the bearing isisolated from the rotor and the high heats produced thereby. In thesecond place, the cooling air within the passageways 36 may directlycontact the bearing to provide direct initial cooling. In the thirdplace, any heat build-np which the bearing does sustain is steadilyconducted outward into the hub 22 and the cooling fins 62, which areconstantly exposed to the moving current of cooling air. Thus, extremely`favorable operating conditions for the bearing are continuouslymaintained.

From examining FIGS. l, 4, and 5, it is to be noted that the sideextremity of the support structure 20 opposite from the outer rimportion 6ft thereof is formed to provide a substantially flat, planarsealing surface 66. This surface is abutted directly against one lateralsurface of the stator means 33, and hence encloses one side of thecylinder cavity 4t) defined therewithin. The opposite side of thecylinder cavity is closed by a similar surface 68 formed integrally withthe end cap structure 46 (FIG. l). It will be observed that a lipportion 70 (FIG. 4) is provided around the outer periphery of thesupport structure 2t), and that the outer housing '72 (FIG. 1) of themotor portion 12 engages this lip to maintain the alignment of thesupport structure with the motor portion. The actual securing of thesupport structure to the motor portion may be accomplished byconventional means, as for example by bolts passing through appropriatebolt holes 74 formed around the periphery of the structure 2d (FIG. 5 Arelieved shoulder 76 (FIG. 4) is formed about the periphery of thesupport structure 2i) on the side of the outer rim 6@ opposite the lipportion 7d, just discussed. The purpose of this shoulder is to receivean enclosing protective Cowling '78 (see FIG. 1) which is preferablyaffixed to or actually a part of the end cap structure 46, and whichextends over the stator means 3S and partially over the supportstructure 211, to substantially completely enclose the pump/compressorportion of the integral apparatus.

By examining FIG. l it will be noted that a baille means 8@ may bepositioned medially between the fan means 18 and the support structure20. Such a baffie is preferably in the general form of a large washer orring, and it is preferably secured to the rim portion 6G of the supportstructure 241, so as to be positioned within the current of Cooling airdrawn by the fan means 13 through the pumping portion of the integralapparatus. By utilizing such a baie, the current of cooling air may bedirected and deflected in a predetermined manner, so as to cause more ofthe cooling air to pass over the bearing hub portion 22 and to circulateinto the spaced areas or passageways 'Ihe value of such a battle meanswithin the integral apparatus of the present invention will be quiteapparent, particularly in connection with the other aspects of the noveicooling arrangement provided herein.

Having now fully set forth the structure of two somewhat differentpreferred embodiments of the invention, and having also fully indicatedthe manner of assembly and the operational features of the integralpump/compressor apparatus, those skilled in the pertinent arts willreadily perceive the advantages made possible thereby.

An integral-type motor-pumping means has been provided which is fullyapplicable to heavy-duty operation, and which has superior operatingcharacteristics and service life when so applied. A novel bearingsupport and retention structure has been disclosed which isolates thebearing from the source of greatest heat at the rotor assembly, whichpositions a sealing means in isolation from the support bearing toprevent lubricants and contaminants from fouling the bearing, and whichaffords uuusually effective cooling of the bearing while in use.Further, the integral apparatus of the invention provides all of theservice benefits of the cantilevered drive shaft, wherein a simple endcap structure may be readily removed to afford complete access to therotor for maintenance and repair purposes.

While I have disclosed herein those specific embodiments and aspects ofthe invention which I find most preferable, it will be apparent thatother similar embodiments as well as certain modifications andvariations in the embodiments which l have shown may be provided, whichsimilarly incorporate the concepts underlying the invention.Consequently, all such further embodiments, variations, andmodifications as are based upon the spirit of the invention are to beconsidered as within the scope of the claims appended herebelow, unlessthese claims by their language specifically state otherwise.

I claim:

1. An integral vacuum pump/air compressor apparatus comprising incombination: a drive shaft; motor means for driving said shaft; a fanstructure mounted on said shaft for rotation therewith; a supportstructure located adjacent said fan structure on the opposite side ofsaid motor means, said support structure secured relative to said motormeans and having portions extending toward and generally surroundingsaid drive shaft to form a hub structure thereabout; a bearing meansretained in position by said hub structure and supporting said shaft indesired alignment; a stator body forming a cylindrical vcavity aboutsaid drive shaft; said stator body positioned adjacent and securedrelative to said support structure opposite said fan structure and motormeans; `a rotor structure mounted upon said shaft for rotation therewithwithin said cavity formed by said body; and an end cap sructurepositioned on the end of said body opposite said support structure andsecured relative to said support structure for enclosing the end of saidbody; said drive shaft having an over-hanging end extendingsubstantially through said rotor structure and cavity and beingunsupported thereat; said support structure and hub having a sealsupport means adjacent said rotor and cavity and a bearing supportportion spaced axially therefrom toward said motor means thereby spacingsaid bearing means from said rotor and cavity for heat isolationpurposes; and said fan structure when rotated by said drive shaftdrawing a current of air into proximity with said hub and bearing meansto provide cooling for the same; said cap structure when removedaffording an unobstructed and easy service access to said rotorstructure.

2. The integral pump/compressor apparatus of claim 1, further includingbaffle means positioned at least partially in the path of said currentof air to deflect a portion thereof into closer proximity with said huband bearing means.

3. The integral pump/compressor apparatus of claim 1, wherein saidsupport structure extending portions denne at least some cooling fins,said fins serving to conduct heat away from said hub and bearing means,and said current of air passing over said fins to cool the same.

4. The apparatus of claim 1, wherein said support structure definespassages communicating with said hub, through which at least a portionof said current of air may pass to facilitate cooling of the hub andbearing.

5. The apparatus of claim 1, wherein said support structure definespassageways communicating with said portion spacing said bearing meansfrom said rotor, at

least a portion of said current of air circulating in said passagewaysand passing over said spacing portion to further cool said bearingmeans.

6. The apparatus `of claim 5, wherein said passageways furthercommunicate directly with said bearing means.

7. The apparatus of claim 3, wherein said support structure furtherdefines passages communicating with said cooling fins and said hub,through which at least a portion of said current of air may pass tofacilitate cooling of the fins and the hub.

8. The apparatus of claim 4, wherein said support structure furtherdenes passageways communicating with said portion spacing said bearingmeans from said rotor, said passages and passageways communicating witheach other, and at least a portion of the said air current passingthrough said passages circulating in said passageways and passing oversaid spacing portion to further cool said bearing means.

9. The apparatus of claim 8, wherein said passageways furthercommunicate directly with said bearing means.

10. The apparatus of claim 8, wherein said support structure furtherdefines cooling fins radiating from said hub and at least in partpositioned in said passages, said fins conducting heat from said hub andbeing cooled by said air current in said passages.

11. The apparatus of claim lil, further including baffle .eanspositioned at least partially in the path of said current of air, todirect and facilitate the passing thereof through said passages, oversaid fins, and into said passageways.

12. An integral vacuum pump/air compressor apparatus of the general typehaving lubricated pumping components comprising in combination: a driveshaft; motor means for driving said shaft; a fan structure mounted onsaid shaft for rotation therewith; a support structure located adjacentsaid fan structure on the opposite side of said motor means, saidsupport structure secured relative to said motor means and havingportions extending toward and generally surrounding said drive shaft toform a hub structure thereabout; a bearing means retained in position bysaid hub structure and supporting said shaft in desired alignment; aseal means generally encircling said drive shaft and retained by saidhub structure in spaced relation from said bearing means; a stator bodyforming a cylindrical cavity about said drive shaft; said stator bodypositioned adjacent and secured relative to said support structureopposite said fan structure and motor means; a rotor structure mountedupon said shaft for rotation therewith generally adjacent said sealmeans and within said cavity; and an end cap structure positioned on theend of said 'body opposite said support structure and secured relativeto said support structure for enclosing the end of said body; said driveshaft having an over-hanging end extending substantially through saidrotor structure and cavity and being unsupported thereat; said sealmeans preventing lubricant and foreign substances from said rotor andcavity from contaminating said bearing means; said spaced relationbetween said seal means land bearing means serving to isolate the latterfrom the heat of the rotor structure and cavity; and said fan structurewhen rotated by said drive shaft drawing a current of air into proximitywith said hub and bearing means to provide cooling for the same; saidcap structure when removed affording an unobstructed and easy serviceaccess to said rotor structure.

13. The integral pump/compressor apparatus of claim 12, wherein saidsupport structure includes a surface generally abutting said cylindercavity and laterally closing the same.

14. The apparatus of claim 13, wherein said end cap structure includes asurface generally abutting said cylinder cavity opposite said supportstructure surface and laterally closing the cavity thereat.

15. The integral pump/compressor apparatus of claim 13, wherein saidsupport structure extending portions define at least some cooling fins,said fins serving to conduct heat away from said hub and bearing means,and said current of air passing over said tins to cool the same.

16. The apparatus of claim 13, wherein said support structure definespassages communicating with said hub, through which at least a portionof said current of air may pass to facilitate cooling of the hub andbearing.

17. The apparatus of claim 13, wherein said support structure definespassageways communicating with said spacing between the seal means andthe bearing means, at least a portion of said current of air circulatingin said passageways and passing over said spacing to further cool saidbearing means.

18. The apparatus of claim 15, wherein said support structure furtherdefines passages communicating with said cooling fins and said hub,through which at least a U portion of said current of air may pass to:facilitate cooling of the fins and the hub.

19. The apparatus of claim 16, wherein said support structure furtherdefines passageways communicating with said spacing between said bearingmeans and said seal means, said passages and passageways communicatingwith each other, and at least a portion of the `said air current passingthrough said passages circulating in said passageways and passing oversaid spacing to further cool said bearing means.

The apparatus of claim 19, wherein sup-port structure further definescooling hns radiating from said hub and at least in part positioned insaid passages, said fins conducti g heat from said `hub and being cooledby said air current in said passages.

21. The apparatus of claim 2%, further including baffle means positionedat least partially in the path of said current of air, to direct andfacilitate the passing thereof through said passages, over said fins,and into said passageways.

22. An integral vacuum pump/air compressor apparatus of the general typehaving oil-less, self-lubricating pumping components, comprising incombination: a drive shaft; motor means for driving said shaft; a fanstructure mounted on said shaft for rotation therewith; a supportstructure located adjacent said fan structure on the opposite side ofsaid motor means, said support structure secured relative to said motormeans and having portion extending toward and generally surrounding saiddrive shaft to form a hub sructure thereabout; a bearing means re tainedin position by said hub structure and supporting said shaft in desiredalignment; a contaminant-isolation barrier plate generally encirclingsaid drive shaft and retained in spaced relation from said bearingmeans; a stator body forming a cylindrical cavity about said driveshaft; said stator body positioned adjacent secured relative to saidsupport structure opposite said fan structure and motor means; a rotorstructure mounted upon said shaft for rotation therewith within saidcavity; and an end cap structure positioned on the end of said bodyopposite said support structure and secured relative to said suppe-rtstructure for enclosing the end of said body; said drive shaft having anover-hanging end extending substantially through said rotor structureand cavity and being unsupported thereat; said support structure and.hub `having a portion spacing said bearing means from said rotor andcavity for heat isolation purposes; said plate obstructing the passageof foreign matter from said rotor and cavity from contaminating saidbearing means; and said fan structure when rotated by said drive shaftdrawing a current of air into proximity with said hub and bearing meansto provide cooling for the same; said cap structure when removedaffording an unobstructed and easy service access to said rotorstructure.

23. The integral pump/compressor apparatus of claim 22, wherein saidsupport structure includes a surface generally abutting said cylindercavity and laterally closing the same.

24,. The apparatus of claim 22, wherein said end cap structure includesa surface generally abutting said cylinder Cavity opposite said supportstructure surface and laterally closing the cavity thereat.

References Cited by the Examiner UNITED SYATES PATENTS 3,060,860 10/1962 Schaefer 2.30-211 3,079,605 2/1963 Thomas et al.

FOREGN PATENTS 71,006 10/1952 Netherlands.

References ied by the Appiieant UNTED STATES PATE'fS 1,122,213 iti/1914Mattman. 2,650,992 9/1953 Forss et al. 2,677,065 4/1954 Heem. 2,704,6933/1955 Schwan. 3,013,167 12/1961 Bobula.

ROBERT M. VJALKER, Primary Examiner.

1. AN INTEGRAL VACUUM PUMP/AIR COMPRESSOR APPARATUS COMPRISING INCOMBINATION: A DRIVE SHAFT; MOTOR MEANS FOR DRIVING SAID SHAFT; A FANSTRUCTURE MOUNTED ON SAID SHAFT FOR ROTATION THEREWITH; A SUPPORTSTRUCTURE LOCATED ADJACENT SAID FAN STRUCTURE ON THE OPPOSITE SIDE OFSAID MOTOR MEANS, SAID SUPPORT STRUCTURE SECURED RELATIVE TO SAID MOTORMEANS AND HAVING PORTIONS EXTENDING TOWARD AND GENERALLY SURROUNDINGSAID DRIVE SHAFT TO FORM A HUB STRUCTURE THEREABOUT; A BEARING MEANSRETAINED IN POSITION BY SAID HUB STRUCTURE AND SUPPORTING SAID SHAFT INDESIRED ALIGNMENT; A STATOR BODY FORMING A CYLINDRICAL CAVITY ABOUT SAIDDRIVE SHAFT; SAID STATOR BODY POSITIONED ADJACENT AND SECURED RELATIVETO SAID SUPPORT STRUCTURE OPPOSITE SAID FAN STRUCTURE AND MOTOR MEANS; AROTOR STRUCTURE MOUNTED UPON SAID SHAFT FOR ROTATION THEREWITH WITHINSAID CAVITY FORMED BY SAID BODY; AND AN END CAP STRUCTURE POSITIONED ONTHE END OF SAID BODY OPPOSITE SAID SUPPORT STRUCTURE AND SECUREDRELATIVE TO SAID SUPPORT STRUCTURE FOR ENCLOSING THE END OF SAID BODY;SAID DRIVE SHAFT HAVING AN OVER-HANGING END EXTENDING SUBSTANTIALLYTHROUGH SAID ROTOR STRUCTURE AND CAVITY AND BEING UNSUPPORTED THEREAT;SAID SUPPORT STRUCTURE AND HUB HAVING A SEAL SUPPORT MEANS ADJACENT SAIDROTOR AND CAVITY AND A BEARING SUPORT PORTION SPACED AXIALLY THEREFROMTOWARD SAID MOTOR MEANS THEREBY SPACING SAID BEARING MEANS FROM SAIDROTOR AND CAVITY FOR HEAT ISOLATION PURPOSES; AND SAID FAN STRUCTUREWHEN ROTATED BY SAID DRIVE SHAFT DRAWING A CURRENT OF AIR INTO PROXIMITYWITH SAID HUB AND BEARING MEANS TO PROVIDE COOLING FOR THE SAME; SAIDCAP STRUCTURE WHEN REMOVED AFFORDING AN UNOBSTRUCTED AND EASY SERVICEACCESS TO SAID ROTOR STRUCTURE.